Trade 18-135 for 16-50?

Does anybody own, or has owned, both the DA 18-135 and the DA* SDM 16-50?

I have the 18-135 for quite some time now, and I think my copy is really good. IQ does fall of in the long end quite quickly though. But from 18 to about 80is it's really good. And I don't really care much about the tele end. Most of my shooting is wide to normal.

Now an opportunity has arisen. I can trade in my 18-135, together with some added cash, for a fairly new DA* SDM 16-50. First I was very excited about the possible upgrade, but when I see the reviews of the 16-50 on this forum, I get very discouraged.

Hi Wilfried, I have both of these lenses which I use on my K-3, and find them both excellent. Optically, the DA* 16-50 is superior, but the then I find the 18-135 more versatile. Indoors with low light, the 16-50 excels. I usually use the 18-135 when I go bushwalking ( and don't want to change lenses ) as the zoom range, and its close focusing make it great for both landscapes and close wildlife images and general " nature " shots. I have both, but would not give up either one. I hope this information is of help to you. Good luck.

But in the real world I promised my wife that I wouldn't expand my lens collection any further.

Very understandable. If I could only have ONE of these lenses, the versatility of the 18-135 would probably sway me towards it. I have taken photographs with the 16-50 that I would not have been able to get with the 18-135, but not that many. If low light shooting is something you want to do without flash, the 16-50 will work beautifully. If you don't need the f2.8, stick with the 18-135.

I haven't used the 16-50, but I do have (currently selling) the 50-135 (its "partner"). Image quality and max. aperture are upgrades but focus speed is MUCH slower -- the "new" focusing motor on the 18-135 is much faster than the old SDM. Forget about autofocus with things that move (without some creativity). Oddly enough, most people indicate a focus speed improvement if they convert it to screw drive although it gets a bit noisier. (Fortunately, my SDM is still working.)

That might be something you want to consider if you decide to purchase the 16-50 -- the conversion can apparently be done with older bodies.

I own both, the 16-50 I have is converted to screw drive die to unreliable SDM on my copy. I find the size s bit off-putting, and owning the da 15, the flare performance at wide angles is disappointing. The 18-135 doesn't go as wide or have the low light performance, but by 24mm at rational f stops or it is hard to tell them apart.

I don't know what I would do... Maybe hold out for a 16-85? Lol. I'm no help.

I don't know what I would do... Maybe hold out for a 16-85? Lol. I'm no help.

No, this is actually very helpful. I had wrongfully dismissed the 16-85 from the start because of the slower and variable aperture. But now judging from user reviews its performance seems to be excellent.

I think I'd keep the 18-135 and find the focal lengths that are really key and hit those spots with good quality primes. It's a common take on the subject. Get yourself a wide, high quality prime, like the DA15 or Samyang 14, etc. What else do you like, portraits? DA*55 or DA50 or FA43, that kind of thing, as budget permits.

The 18-135 covers a ton of zoom range with high IQ, weather resistance, great AF performance, small physical package. The 16-85 is appealing as well but it's larger, heavier, and I kind of like the 18-135's images more myself.

I think I'd keep the 18-135 and find the focal lengths that are really key and hit those spots with good quality primes. It's a common take on the subject. Get yourself a wide, high quality prime, like the DA15 or Samyang 14, etc. What else do you like, portraits? DA*55 or DA50 or FA43, that kind of thing, as budget permits.

I've got a lot of very nice primes. But I'm very careful with them. I just want one WR zoom that's going to take all the punishment of rain, dust, snow, etc...

Originally posted by pres589

The 18-135 covers a ton of zoom range with high IQ, weather resistance, great AF performance, small physical package. The 16-85 is appealing as well but it's larger, heavier, and I kind of like the 18-135's images more myself.

That's interesting, what aspect exactly makes you prefer these images? This is what I'm afraid of, selling my excellent copy of the 18-135 for something that's going to make me miss it.

It's hard to say. Nothing technical really, just user shared images, I think the 18-135's look quite nice for the most part. Honestly the 16-85 might be overly sharp? I can't explain it and maybe it's not even a thing. I kind of can't understand why the 16-85 was developed when the 18-135 already existed and some other areas of the lens lineup could have been targeted instead, like a better 16-50 or a good prime in the 20's, etc.

My two cents like always and I'm curious what others come back with. I know this has been discussed in the past between these two lenses.

I've owned both.. I'm selling my gear and have already sold the 16-50mm and will likely sell the 18-135mm soon.

But I'd say the 18-135mm is as sharp stopped down to about f/5.6 to f/8 (depending on your focal range) and is a little smaller and a lighter. The DC motor is more reliable too in my experiences compared to the SDM in the 16-50mm.

For a walkaround/vacation lens I think I like the 18-135mm better but I do enjoy getting down to 16mm -- that extra 2 mm is noticeable on the wide/short end of the focal range. But I always long for more range on the wide end where the 18-135mm makes up for it.

f/2.8 speed is nice but I found 2 copies of the 16-50mm I've owned needed to be stopped to 3.2 or slower before it really sharpened the view to my liking. Still, having a rather fast fixed aperture through the focal range is a treat and helpful for indoors shooting.

I have the 18-135 and have used it quite a bit. It's very dependable, reasonably light, and the long zoom range makes it ideal for travel or when I go hiking. However when I have the opportunity I will swap out for my Sigma 18-50 f/2.8 as it is sharper and faster, although heavier and noisier. I also use my DA-15 a lot. I've been trying to figure out what my ideal zoom would be. I think maybe the 16-85 and sell the 18-135 or get the 20-40 for a walk around and keep the 18-135 for hikes and travel. There is no right answer. I will not buy the DA16-50 SDM until they replace it with a non-SDM version. It's just too expensive for an unreliable lens. I've previously owned the 17=70 which is a wonderful zoom range but it was SDM and it failed me twice before I sold it (with full disclosure). Despite some suggestion that Pentax has fixed or Improved the SDM system, I won't touch them unless it's used and very cheap. Good luck with your lens selection.

I've had both. The 16-50 I had was a good copy of the lens and well worth it to own. It was the better lens image quality wise and the constant f/2.8 was great for indoor photography. The 18-135 is a great revel zoom. If you pixel peep you will notice the difference, but for web shots or small prints/collages (we do photo books of our vacations) the 18-135 works just fine. But when it came to sell some kit to help fund my K-1, I decided to sell the 16-50, because I do not do a lot of event type photography, my primes fill the need for interior photography, and the 18-135 is just a versatile little lens especially when I go on a hike or travel.

Last edited by wstruth; 10-04-2017 at 06:08 AM.
Reason: cleaning it up

That's a tough decision. I use my Tamron 17-50 f/2.8 inside and my DA 18-135 outside, so I'd have a hard time getting rid of either. If I had to choose I'd probably go with the Tamron 17-50 because most of my shots are indoors in low light and the constant f/2.8 really helps. If I didn't have issues with low light the WR, range, and silent DC motor are big enough advantages to stick with the 18-135. In pixel peeping the 17-50 can be sharper, especially at the edges, but I'm very happy with the 18-135 images regardless.

Since you have a good copy of the 18-135 I'd say hold onto it. If you need more light performance look into a used Tamron 17-50. They're cheaper than the DA* 16-50 and basically equivalent performance. The DA* also has a history of SDM failure that makes me nervous.

The only way I would suggest trading in the 18-135 is if you look through your pictures and barely any of them are beyond 50mm. If you have any really great shots you couldn't have taken between 17-50 that might sway your decision. If most of your favorite shots are between 17-50 and noisy due to high ISO, an f/2.8 lens might be just what you need.

I own both. The 18-135 is a nice travel lens (lightweight, relatively quick autofocus). The 16-50 is definitely sharper, and the autofocus speed is almost as fast, and very accurate, even in low light. Despite its increased weight, I use the 16-50 much more. The image quality of the 16-50 is in a different league. I sold the 21mm and 50mm primes, as the IQ of the 16-50 was superior, and the “normal” zoom range more versatile. I’ve not had a problem with the SDM, and would ask Uncle Vanya to convert it if it were to fail.